U.S. Pat. No. 3,890,327, granted to Joel Berger on June 17, 1975, discloses the compound trans-1,2,2,3,4,4a,8,9,14a-octahydropyrido[4', 3':2,3]indolo[1,7-ab][1]benzazepine: ##STR1## and its use as an analgesic. This compound is a convenient starting material for virtually all of the compounds from within the scope of the present invention.
Copending U.S. patent application Ser. No. 596,851, filed July 17, 1975, now U.S. Pat. No. 4,018,930, issued Apr. 19, 1977 by Joel G. Berger, (which is a continuation-in-part of U.S. patent application Ser. No. 422,615, filed Dec. 6, 1973 and now abandoned) discloses certain novel indolobenzazepines of the general formula: ##STR2## and their pharmaceutically suitable acid addition salts, where R is certain organic radicals, which indolobenzazepines are useful as analgesics and sedative-tranquilizers. In particular, U.S. Ser. No. 596,851 discloses compounds of formula II where R is, among other things, a C.sub.3 -C.sub.8 oxoalkyl side chain.
U.S. Pat. No. 3,932,650, granted to Charles Adams on Jan. 13, 1976 (which is a continuation-in-part of U.S. patent application Ser. No, 325,352, filed Jan. 22, 1973 and now abandoned) discloses certain other compounds of formula II above wherein R is certain other organic radicals.
Finally, U.S. Pat. Nos. 3,373,168 and 3,457,271 disclose certain compounds of the formula: ##STR3## wherein R is alkyl of 1 to 7 carbon atoms and the compounds have the cis configuration of the 4a and 14a hydrogens. These compounds are disclosed as antidepressants.